<!doctype html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport"
          content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>jsonp</title>
</head>
<body>
<button id="btn">按钮</button>
<script>
    var btn  = document.getElementById('btn');
    function callback(res) {
        console.log(res)
    }
    btn.onclick = function () {
        var script = document.createElement('script');
        script.type = 'text/javascript';
        script.src = 'http://www.1808-test.com/1.php';
        document.head.appendChild(script);
    }
</script>
</body>
</html>